1. Field of the Invention
The present invention relates to a vehicle abnormality diagnosis system for performing abnormality diagnoses, such as diagnosing malfunctions and predicting the service life of vehicles such as construction machines.
2. Description of the Related Art
In order to improve the reliability of a construction machine, carrying out abnormality diagnoses, such as diagnosing engine malfunctions, determining the extent of engine deterioration and predicting engine service life (predicting overhaul times), is essential. On the occasion when an abnormality diagnosis is performed, it is necessary to acquire, under the same operating conditions (condition that the machine is operated at a rated point on the torque curve), operating parameters the values of which change during construction machine operation, such as engine blow-by pressure, number of rotations, and fuel injection quantity. This is because it is not possible to compare data, and diagnose an abnormality unless operating parameters can be acquired under the same operating conditions.
Conventionally, operating parameters have been acquired in the following manner.
(a) First, the construction machine is shut down during work, and work is suspended.
(b) Then, as many measuring instruments, such as a pressure gauge and tachometer, as the number of operating parameters to be measured are mounted to an engine.
(c) In a state where a load is applied to the stopped construction machine and the torque converter is made to stall, engine speed and fuel injection quantity are carried to the rated point.
(d) If the value of an operating parameter achieves saturation and is stable, the data measured by the measuring instrument are read out and recorded.
However, shutting down the construction machine, and suspending work for the sake of taking measurements as mentioned in (a) above brings about reduced work efficiency.
Further, a person (serviceman) skilled in measurement work is needed to perform the work of mounting the measuring instruments for taking measurements, controlling the construction machine so that a fixed operating condition is achieved, and recording measurement data as mentioned in (b), (c), and (d) above,. Consequently, personnel costs will be increased for measurement purposes.
Further, as indicated in (c), (d) above, because measurements of operating parameters are taken in a state in which the construction machine has been shut down, and a torque converter has been made to stall, heat is generated by the torque converter. For this reason, a fixed operating state cannot be maintained for a long period of time (the limit is 20 seconds at the most). As a consequence, problems such as the following are incurred.
FIG. 6 shows conventional operating parameter measurement results. The horizontal axis is the time axis, and the vertical axis indicates the size of the respective operating parameters. FIG. 6 shows a case in which the respective parameters of engine speed, governor rack position (voltage value), pressure, exhaust temperature, oil temperature, and blow-by pressure are obtained. When engine speed and governor rack position (voltage value) rise, and a stable state (rated point) is achieved, the blow-by pressure also stabilizes, as indicated by S, and measurements can be taken at a time ts during the period S when blow-by pressure is stable. Furthermore, in the figure, blow-by pressure is pulsating, but measurements are taken after creating a stable waveform by performing signal processing, such as causing the signal to pass through a low pass filter. Governor rack position refers to a voltage value, which indicates the control rack position of an electrical governor of a fuel injection pump.
As shown in the same FIG. 6, out of consideration for heat generation by the torque converter, the stable period S after engine speed and governor rack position (voltage value) have risen all the way is very brief. Consequently, exhaust temperature does not reach saturation, and accurate data cannot be collected in the time ts.
As described above, when using the conventional method, wherein measurements are taken in a state in which the construction machine is shut down, depending on the type of operating parameter, saturation cannot be achieved, and accurate data cannot be collected.
In recent years, there have been attempts to acquire an operating parameter of a construction machine in time series fashion, and to carry out an abnormality diagnosis on the basis of the acquired time series data. Consequently, in addition to periodically making engine operating conditions fixed operating conditions, it is necessary to periodically acquire operating parameters. For this reason, as indicated in (a) above, the construction machine must be periodically shut down, and work must be suspended, causing the drop in work efficiency to become even more serious.
With the foregoing in view, a first object of the present invention is to enable the measurement of an operating parameter under a fixed operating condition without bringing about rising personnel costs, and without causing construction machine work efficiency to drop, and to enable the reliable acquisition of accurate data.
Further, conventionally, engine blow-by pressure has been detected, and an engine abnormality diagnosis has been made based on the size of the detected blow-by pressure. Blow-by pressure is a useful operating parameter for quantitatively detecting damage done to an engine.
Therefore, a second object of the present invention is to diagnose an engine abnormality more accurately by quantitatively detecting damage done to an engine using a new operating parameter related to blow-by pressure.
To achieve the first object of the present invention, a first invention is a vehicle abnormality diagnosis system for acquiring an operating parameter under a specified operating condition of a vehicle, a value of the operating parameter changing during an operation of the vehicle, and for diagnosing a vehicle abnormality on the basis of the value of the acquired operating parameter, wherein either a specified point or a specified area, at which the vehicle operating condition becomes the specified operating condition, is set beforehand from among points or areas on a travel route along which the vehicle travels, and an operating parameter of a point in time, at which the vehicle passed either the specified point or the specified area, is acquired, and an abnormality of a vehicle is diagnosed on the basis of a value of the acquired operating parameter.
According to the first invention, as shown in FIG. 5, either a specified point Q or a specified area Ar, at which an operating condition of a vehicle 50 becomes a specified operating condition, is set beforehand from among either each point or each area on a travel route 51, which a vehicle 50 travels.
As shown in FIG. 11, an operating parameter P of a point in time ts1, ts2, ts3, ts4 . . . , tsn, at which a vehicle 50 passes either a specified point Q or a specified area Ar, is obtained.
Then, as shown in FIG. 12, a vehicle abnormality is diagnosed on the basis of the values of these obtained operating parameters P (maximum values Pmax).
According to the first invention, since an operating parameter P is obtained under a specified operating condition while a vehicle 50 is travelling, there is no need to stop the vehicle for taking measurements. Consequently, work is not suspended, and a drop in work efficiency is not incurred. Further, since there is no need to perform the work of mounting measuring instruments, controlling a vehicle so that a fixed operating condition is achieved, or recording measured data, a person (serviceman), who is skilled at measurement work, is not required. Consequently, personnel costs do not rise.
Further, because an operating parameter can be obtained during vehicle 50 travel at a point, at which it becomes a specified operating condition, it is possible to collect accurate data in a state in which an operating parameter achieves saturation and is stabilized.
As described above, according to the first invention, the measuring of an operating parameter under a fixed operating condition can be performed without bringing about a rise in personnel costs, and without causing a drop in work efficiency, and accurate data can be reliably obtained.
Further, to achieve the first object of the present invention, a second invention is vehicle abnormality diagnosis system for acquiring an operating parameter under a specified operating condition of a vehicle, a value of the operating parameter changing during an operation of the vehicle, and for diagnosing a vehicle abnormality on the basis of the value of the acquired operating parameter, comprising setting means for setting beforehand from among points or areas on a travel route along which the vehicle travels, either a specified point or a specified area at which an operating condition of the vehicle becomes the specified operating condition; position detecting means for detecting the location of the vehicle when the vehicle is travelling on the travel route; trigger signal generating means for generating a trigger signal when a location detected by the position detecting means becomes a location corresponding to either the specified point or specified area; operating parameter acquiring means for acquiring an operating parameter in accordance with the trigger signal being generated; and abnormality diagnosing means for diagnosing a vehicle abnormality on the basis of a value of the acquired operating parameter.
According to the second invention, as shown in FIGS. 2 and 5, either a specified point Q or a specified area Ar, at which an operating condition of a vehicle 50 becomes a specified operating condition, is set beforehand from among points or areas on a travel route 51, which a vehicle 50 travels (Step 101).
Then, a location of vehicle 50 is detected when vehicle 50 is traveling on travel route 51.
Then, a trigger signal is generated when a detected location becomes a location corresponding to either a specified point Q or a specified area Ar (Steps 105, 106).
Then, an operating parameter is obtained in accordance with a trigger signal being generated (Step 107).
In this manner, as shown in FIG. 11, there is obtained an operating parameter P of a point in time ts1, ts2, ts3, ts4 . . . , tsn, at which vehicle 50 passes either a specified point Q or a specified area Ar.
Then, a vehicle abnormality is diagnosed on the basis of the values of these obtained operating parameters P (maximum values Pmax) (Steps 108, 109).
According to the second invention, the same effect as the first invention is achieved.
Further, a third invention is a vehicle abnormality diagnosis system according to either the first invention or the second invention, wherein the operating parameter is sequentially stored by corresponding the operating parameter to a time at which the operating parameter was acquired, and diagnosis of a vehicle abnormality is performed on the basis of time series data of the stored sequential operating parameters.
According to the third invention, as shown in FIG. 12, an operating parameter (maximum value Pmax) is sequentially recorded by making it correspondent to an acquired time (each xcfx84 time). Then, a vehicle abnormality is diagnosed on the basis of time series data DT of the recorded sequential operating parameters.
That is, according to the third invention, as shown in FIG. 11, there is acquired an operating parameter P of a point in time ts1, ts2, ts3, ts4, . . . , tsn, at which vehicle 50 passed either a specified point Q or a specified area Ar. Then, a maximum value Pmax of the operating parameter P is determined at xcfx84 time. Then, as shown in FIG. 12, a maximum value Pmax of each xcfx84 time of the operating parameter P is sequentially recorded by making same correspondent to a time (each xcfx84 time). Then, a vehicle abnormality is diagnosed by comparing time series data DT of the recorded sequential operating parameter maximum values Pmax against threshold values Pc1, Pc2, Pc3.
In this manner, according to the third invention, an operating parameter P is periodically acquired under a fixed operating condition while a vehicle 50 is traveling, and time series data DT is obtained. Consequently, it is possible to avoid periodically shutting down vehicle 50. In accordance therewith, it is possible to prevent significant drops in work efficiency due to periodic suspension of work.
Further, to achieve the first object and second object, a fourth invention is vehicle abnormality diagnosis system for acquiring data related to blow-by pressure under a specified operating condition of a vehicle, a value of the data changing during an operation of an engine of the vehicle, and for diagnosing a vehicle abnormality on the basis of the value of the acquired blow-by pressure-related data, wherein either a specified point or a specified area, at which blow-by pressure rises and the blow-by pressure overshoots, is set beforehand from among points or areas on a travel route along which the vehicle travels, and a blow-by pressure overshoot quantity of a point in time, at which the vehicle passes either the specified point or the specified area, is acquired, and a vehicle abnormality is diagnosed on the basis of a value of the acquired blow-by pressure overshoot quantity.
According to the fourth invention, as shown in FIG. 5, there is set beforehand, from among points or areas on a travel route 51, which vehicle 50 travels, either a specified point Q or a specified area Ar at which blow-by pressure rises, and blow-by pressure overshoots.
Then, as shown in FIG. 11, there is acquired a blow-by pressure overshoot quantity xcex94P at a point in time ts1, ts2, ts3, ts4, . . . , tsn, at which vehicle 50 passed either a specified point Q or a specified area Ar. Then, a maximum value Pmax of the operating parameter P is determined at xcfx84 time. Then, as shown in FIG. 12, a vehicle abnormality is diagnosed on the basis of these acquired overshoot quantities (maximum value xcex94Pmax).
According to the fourth invention, the same effect as the first invention is obtained. Furthermore, according to the fourth invention, as shown in FIGS. 9(a), 9(b) and 9(c), the state of engine wear (amount of damage) is quantitatively detected from differences in the sizes of blow-by pressure overshoot quantities xcex94P1, xcex94P2, xcex94P3. In accordance therewith, an engine abnormality can be more accurately diagnosed by comparison with a case in which a diagnosis was performed on the basis of blow-by pressure.
Further, to achieve the second object, a fifth invention is vehicle abnormality diagnosis system for acquiring data related to blow-by pressure, a value of the data changing during an operation of an engine of a vehicle, and for diagnosing a vehicle abnormality on the basis of the value of the acquired blow-by pressure-related data, comprising blow-by pressure overshoot quantity measuring means for measuring an overshoot quantity when blow-by pressure rises and the blow-by pressure overshoots; and abnormality diagnosing means for diagnosing a vehicle abnormality on the basis of a value of the measured blow-by pressure overshoot quantity.
According to the fifth invention, as shown in FIGS. 9(a), 9(b) and 9(c), the state of wear, or amount of damage of an engine is quantitatively detected from differences in the sizes of blow-by pressure overshoot quantities xcex94P1, xcex94P2, xcex94P3. In accordance therewith, an engine abnormality can be more accurately diagnosed compared to a case in which a diagnosis was performed on the basis of blow-by pressure.